Windows thin client on Linux Desktop

Using WINE, Sidenet and even CrossOver Office, I have repeatedly tried to run the destop client to our accounting package. The server is Windows 2000. Drive mapping works fine. The app installs from the mapped drive fine. It even connects to the database on the server. But it all stops with the message “Cannot connect to license server.” Is there some special trick to handshaking the license registry on 2k?